Dental tool.



C. M. CARR.

DENTAL TOOL.

1913893550 APPLICATEQN FILED OCT. 12, 1905. Patented May 4: v

2 SHEETS-SHEET 1.

IT 1 i f By I v 7 C. M. CARR.

DENTAL TOOL. APPLICATION FILED OCT. 12. I905.

Patented May 4., 1915.

2 $HEETSSHEET 2.

' 4 [270671 for I M1240 CAS SIUS M. CARE, OF FORT WORTH, TEXAS.

DENTAL TOOL.

Specification of Letters Patent.

Patented May 4, 1915.

' Application filed October 12, 1905. Serial No. 282,462.

To all whom it may concern Be it known that I, CASSIUS citizen of the United States of America, residing at Forth Worth, in the county of Tarrant and State of Texas, have invented certain new and useful Improvements in Dental Tools; and I do hereby declare that the following is a full, clear, and exact description of the invention, such as will enable others to make and use the same, reference being had to the accompan ing drawing, forming a part of this s'peci cation.

In carrying out my invention, I provide a series of tools each adapted for use upon a predetermined shaped portion of the tooth and each has a cutting edge and a guiding pbrtion. The guiding portion serves to engage with the tooth in advance of the cutting edge to steady the same, While the cutting edge is in the line of the axis of the handle, whereby the instrument has no tend- 'ency to turn when in use and cuts after the the position of the cutting blade in passing over the irregular surfaces, and, Fourth. To prevent injury to the tissue surrounding the teeth in the operation-of the tool.

' The invention accomplishes the removal of scale from the teeth, which scale results in the inflammatory conditions of the gum and pus formations and consequent loosening of the teeth, and which is known as pyorrheae The construction'of the tool will be first fully described and then its operation shown and the invention specifically pointed out in the claims.

In the drawings Figure 1 is a view of the novel tool showing the handle, the. shank and its rounded end and cutting edge and its surface posterior to the cutting edge in perspective. Fig.2 is a side view of the tool assoc-n in Fig. 1. Fig. 3 is an enlarged broken view in perspective of the outer end portion of the shank showing the cutting M. I CARR, a

blade? Fig. 4 is an end view of the tool enlarged showing the scale removing cutting edge of the tool and its position in relation to the longitudinal axis of the handle. Figs. 5 and 6 are side and Fig. 7 a front view of the tool showing modifications of the shank. Figs. 8 and 9 are enlarged end views of the tool looking in the direction of the handle showing alternate positions of the cutting edge of the tool to that seen in Fig. 4. Figs. 10 and 11 are enlarged views of upper molar teeth, and, Figs. 12, 13 and 14 are enlarged views of central incisors showing the application of the tool for the removal of scale from the various portions of the teeth.

Similar numerals of reference indicate corresponding parts in all the figures of the drawing.

Referring to the drawings, 16 indicates the handle of the tool, the longitudinal surface ofwhich for the purpose of illustration is octagonal in cross section ;'17 indicates the bulge of the tool at the end of and in a'direct line with the handle. With the outer end of the bulge is connected the shank 18, of the tool which is bent laterally at said-point of connection in a slight degree and then bent ata point smaller in circumference than the bulge l7 and'is bent intermediate its outer end and the bulge at an angle and said outer end extended to a position coincident with a direct line projected from and extending through the longitudinal axis of the handle 16, of the tool. The outer end back portion of the shank 18, is rounded and bent in a curved line or convexed at 19, to the said line extending through the longitudinal axis of the handle, and in a corresponding direction to the bent portion of the body of the shank 18 in the requisite degree. The surface of the face or forwardconcave portion 19 of the said curved portion 19 is flat, the surface being excavated transversely with an increased depth in a slight degree toward the cutting blade at the outer end of the shank. The extreme end of the curved portion 19, of the shank is bent or upset in an outwardly curved line of direction to said portion 19, forming a projection seen at 20, and extending forwardly of said concave portion 19, and the lower surface of said projection 20 extends transversely to the flat concave face surface 19 outwardly forming the cutting edge 21, which edge extends to and extending through the longitudinal axis of the handle and in the position illustrated in Fig. 1 at an obtuse angle to the said line projected from said longitudinal axis of the handle. The tool .as shown in Fig. 1 is provided with a long bent shank and an outer bent end forming compound curves or bends, available in the operation of removing scale from the lower third of the root of teeth, the length of which shank maybe reduced when required for application to the upper third of a tooth and adjacent to the crown.

In operation the shank is introduced in the alveolar process with the cutting edge of the tool directed toward the tooth and the scale and in order to effectively remove the scale the instrument is first directed to the lower third as seen in Fig. 12, for which the long shank in Fig. l, with its concave excavated portion in contiguity with the root the concave surface of the shank posterior to the cuttingedge bearing upon the side of the lower third of the tooth and a drawing movement imparted to the handle of the tool in which movement the scale is attacked and dislodgment effected coincident with the posterior curved surfaces and'when the scale is removed from the gum or process the operation is continued and upon the same surface of the tooth from which the scale is removed until the entire surface of the dentine is perfectly smooth. I11 this operation the cutting edge of the tool being in line with the longitudinal axis of the handle the drawing movement meets no counteracting leverage and this movement in the various positions of the handle may be performed with a slight grasp of the instrument by the hand, and at the same time a draw out is imparted to the scale and then to the surfaces of the tooth planing the surfaces until these surfaces are smooth. The results attained are readily appreciable and marked from the fact that in the use of the ordinary scale removing tool the cutting edges of these tools cause irregular engagements and leave the surface of the tooth in a rough condition. In successfullyremoving the scale from various portions of the tooth the angle of the cutting edge 21 is conveniently varied as seen in Figs. 8 and 9, in which the cutting edges are shown disposed .in coincident positions to the surface of the angles of the handle as shown octagonal and in cross section and in series the varied positions are numerically the same.

In the modification as seen in Fig. 5 the portion of the shank posterior to the cutting edge of the tool is straight as at 27 and in Fig. 6, the said end is formed with a convexed portion 22, posterior to the cutting edge and in Fig. 7 the flat concave surface posterior to the cutting edge is located upon the side of the shank. As before. stated the shank may be made long or short as the occasion requires, the cutting edge always beingv upon the same side of the shank as the posterior fiat surfaces. In order to remove the scale from the middle third of the tooth as seen in Fig. 13, the tool provided with the shank which is the modification as seen in Fig, 5 is employed, following which the scale is removed from the upper third as in Fig. ll, in which the modification of the tool as seen in Fig. ('5 is employed to which the shank is particularly adapted, which being short in length the convexed excavated portions of the shank posterior to the cutting edge permit the cutting edge to enter the depression at the neck of the tooth and effect complete removal of the scale.

In the various operations the scale is not left in the alveolar cavitiesbut is drawn out by the cutting edge of the tool and the curved or upset end 20, of the tool prevents lacerationof L'Lro tissues.

In removing the scale from the molar as seen in Figs. 10 and 11 the adaptability of the tool is manifest particularly around the .upper third between the roots, the scale being first removed by the application of the tool as seen in Fig. 1, the concave surfaces of the shank posterior to the cutting edge fitting the convex surface of the molar and in Fig. 11, the modification as seen at 22 in Fig. 6 being adapted to fit the concave surface of the molar. In these varied forms in the construction of the tool I am enabled to reach the surfaces of all roots of teeth and remove all foreign substances and leave the dentine with a smooth polished surface .without lacerating the surrounding tissue,

and thus obviating the inflamed condition of the parts adjacent thereto thus offering the highest degree of resistance to the recurrence of the deposit on the tooth; the position of the cutting edge with the various modifications of the shank affording the most expeditious and efficient means of operating and securing results hitherto unattainable. Such other modifications may be employed as are within the scope of the invention.

Having fully described my invention what I now claim as new and desire to secure by Letters Patent is,

1. A scale removing dental tool compris ing a handle, a compound bent shank, and, adjacent the end of said shank, a cutting edge extending to and coincident with a line projecting from and extending through the longitudinal axis of the handle, said shank being formed adjacent the cutting edge with a guide surface which transversely comprises substantially straight line elements and which longitudinally conforms to the shape of the tooth surface to be operated 'upon and is adapted to rest thereon in contact with the tooth surface in such manner as to prevent the cutting edge from scraping the dentine of the root of thy tooth, the guide surfaces, cutting edge and the end --of the shank beyond the'ciltting edge being so'shaped that when cutting, the tool must rest upon the tooth at two points, one point being imthecutting edge and the other point being in the guide surface adjacent thereto, so that the tool must be operated by a drawing motion, the point of contact in the guide surfa'ce necessarily going ahead of the cutting edge, thus causing the tool to out after the manner of a Japanese plane.

2. Tools for the treatment of teeth comprising a series of straight handles, each tool adapted for use upon a predetermined shaped portion of the tooth and each having a. cutting edge and a guiding portion, the guiding portion serving to engage with the tooth in advance of the cutting edge to steady the same, and the cutting edge being in the line of the axis of the handle whereby the instrument has no tendency to turn when in use, and planes as contradistinguished from scraping the surface.

, 'CASSIUS M. CARR.

Witnesses:

WM. VALTER BRADY, E. W. METCALF. 

